Electric-arc lamp.



No. 663,346.- W Patented Dec. 4, I900. W. C. JOHNSON &. A. WUNDERLICH.

ELECTRIC ARC LAMP.

(Applicnion filed Sept. 10, 1900.) (No Model.) 2 Sheats8hoei l.

THE NcRms PETERS co. PnOYO-LITHQ, WASHINGTON. 11cv No. 663,346. Patented Dec. 4, I900.

' W. C. JOHNSON & A. WUNDERLICH.

ELECTRIC ARC LAMP.

(Applicnbion filed. Sept. 10, 1900.)

2 Sheets-Sheet 2.

(lo Iodel.)

UNITED STATES PATENT OFFICE.

IVALTER CLAUDE JOHNSON AND ADOLPH WUNDERLICH, OF LONDON, ENGLAND.

ELECTRIC-ARC LAM P.

SPECIFICATION forming part of Letters Patent No. 663,346, dated December 4, 1900.

Application filed September 10, 1900 Serial No. 29,564. (No model.)

To aZZ whom it mciy concern:

Be it known that we, WALTER CLAUDE JOHNSON, a citizen of Eugland,residing at The Dignaries, WVestcombe Park, Blackheath, London, and ADOLPH WUNDnRLIoH, a citizen of the United States, residing at The Limes, Coleraine road, Westcombe Park, Blackheath, London, in the county of Kent, England, have inventedacertain new and useful Improvement in Electric Arc Lamps, (for which we have applied for a patent in Great Britain, dated February 16, 1900, No. 3,108,) of which the following is a specification.

In our Patent No. 638,125 we have described a clutch for the carbons of an electric-arc lamp operated by the core of a solenoid.

Our present invention consists in an improved construction of the solenoid and its core in such a manner that the lamp can be worked by alternating as well as by continuous currents.

Figure 1 of the accompanying drawings is a vertical section of the upper part of the lamp and of the improved solenoid and core, and Fig. 2 is a horizontal section on the line A A of Fig. 1.

The core a of the solenoid is inclosed on two sides and above and below by a yoke 79, consisting of laminae of soft iron held together by rivets c passing through them. Through holes bored vertically through the end of the yoke 19 and through the bobbin (1, on which the coil is wound, extends a tube 6 of nonmagnetic metal. Within this tube is free to slide the core f, which consists of a tube having six pairs of projecting ribs 9, the whole made preferably of aluminium for the sake of lightness, and the space between the ribs of each pair is filled with lightlypacked laminzee', of soft sheet-iron, extending the whole length of the core. Near each end of the core a shallow recess is turned to hold packing j, which rubs on the internal surface of the tube 6 as the core moves up and down within it. The core is attached by a spring 70 to deaden shocks to the brake-piston Z, which carries the clutch-pieces h, described in our previous patent. By constructing the yoke b and the ribs iof the core of soft sl1eetiron laminated these parts are readily magnetized and demagnetized, as required for operating with alternating currents.

Having thus described the nature of this invention and the best means we know of carryi ug the same into practical effect,we clai m- For an electric-arc lamp a solenoid and core consisting of a laminated iron yoke inclosing the coil, and a tubular core having ribs of laminated iron, whereby the lamp is rendered capable of operating with alternating currents, substantially as described.

In testimony whereof we have hereunto set our hands in presence of two subscribing witnesses.

WALTER CLAUDE JOHNSON. ADOLPI'I l/VUNDERLICH.

Witnesses:

GERALD L. SMITH, W. M. HARRIS. 

